Electric air-compressor.



A. J. POGOGK & B. E. ALLGIRE.

ELECTRIC AIR COMIEESSOR.

APPLICATION FILED umza, 1905.

918,194. Patented Apr. 13, 19109.

7 SHEETS-SHEET 1.

A. J. POGOCK & R. E. ALLGIRE.

ELECTRIC AIR COMPRESSOR.

APPLICATION FILED AUG.Z5, 1905.-

Patented Apr. 13, 1909.

31 wento'm/ ,iugushnej Pmack A. J. POGOCK & R. E. ALLGIRE.

ELECTRIC AIR COMPRESSOR.

APPLICATION TILED AUG. 25, 1905.

Patented Apr. 13,1909.

7 SHEETS-SHEET 3.

A. J. POCOGK & R. E. ALLGIRE.

ELECTRIC 'AIR COMPRESSOR.

APPLICATION FILED AUG.25, 1905.

Patented Apr. 13, 1909.

7 SHEETS-SHEET 4.

A. J. POGOCK & R. E. ALLGIRE. ELECTRIC AIR COMPRESSOR.

APPLIGATIONIPILED AUG. 25, 1905.

, 918,194. v Patented Apr. 13, 1909.

7 SHEETS-SHEET 5.

W "ll/1710mm, 4, lllllll/lllffl' a 5J1 wantow w m Rulwxk ikmyoixim .i, a

Patented Apr. 13, 1909.

7 SHEETS-SHEET 6.

I l l l l o A. J. POCOGK & R. E. ALLGIRE. ELECTRIC AIR COMPRESSOR.

APPLICATION FILED AUG. 25, 1905.

A. J. POGOCK & R. E. ALLGIRE.

ELECTRIC AIR COMPRESSOR. APPLICATION FILED AUG. 25, 1965.

91 8, 1 94 Patented Apr. 13, 1909.

I SHEETSSHEET 7.

5 i manic b4 g l D Wu Rmmxm 3 was :16,

AUGUSTINE J. POGOGK AND RICHARD E. .ALLGIRE, F DAYTON, OHIO, ASSIGNORS o THE- tive 'UNITED STATES PATENT OFFICE.

PLATT IRON WORKS COMPANY, OF DAYTON, OHIO, A CORPORATION OF OHIO.

ELECTRIC AIR-COMPRESSOR.

Application filed August 25, 1905. Serial No. 275,819

To all whom it may concern:

Be it known that we, AUGUSTINE J. P0-

000K and RICHARD E. ALLGIRE, citizens of the United States, residing. at Dayton, in the county of Montgomery and State of Ohio,-

haveinvented certain new and useful Improvements in Electric Air-Compressors, of which the'foll'owing is a specification.

Our invention relates to improvements in air compressors, and particularly relates to com ound, electrically driven compressors ca a le of developing high pressures.

. The object of the invention is to provide a compressor which will be compact, comparay light inweight, self-contained and well balanced, and so constructed that the various parts will-be easily accessible.

A further object is to provide a compound compressor in which the various compression cylinders will be directly operated from an electric motor incorporated in the structure.

B the compression of air there is developed considerable heat.

A further object of the invention is to provide efiicient means after each compression for absorbing the heat developed, reducing the temperature to substantially normal, and thereby reducing the bulk.

A further object is to provide a rotary or centrifugal force-pump connected directly to the motor-shaft, by which the cooling medium will be supplied to the various intercoolers and cylinders.

A further object is do provide a structure which will ermit the successful and eflicient use of the cotch cross-head, which has generally been found inefiicient.

A further object is to provide means whereby oil under pressure will be supplied to the various beari gs.

With the above primary and other incidental objects in view, the invention consists of the construction, mechanism and I arts, or their e uivalents, hereinafter descri ed and set fort in the claims.

Referring to the drawings, Figure 1 is a side 'view ofa four-stage electric air compressor, as viewed from the first and fourth cylinder side. Fig. 2 is an end View of same as viewed from the right in Fig. 1. Fig. 3 is a sectional view through the low and high pressure cylinders and the after-cooler. Fig. 4 is a longltudinal sectional view through the.

secondand third cylinders and the second inter-cooler. Fig. 5 is a view of the arma- Patented. April 13, 1909.

ture and crank shaft, showin in dotted lines the oil channel therein, and the oil pump attached. Fig; 6 is an end view of same. .Fig. 7 is a transverse vertical sectional view of the bearing for the armature shaft. 9 Fig. 8 is a sectional view of the crank-casing sho the crank, the oil-pump, and a lon 'tudinal section of the'arinature bearing. ig. 9 is a horizontal view of the armature bearing. Fig. 10 is a vertical sectional view of the oilpump. Fig, 11 is an elevation of the oilump with a portion of the casing removed.

ig. 12 is a vertical sectional view of the totary pump for the cooling medium. 13 is an elevation of samewith a casing removed. Like parts are represented by similar characters of reference throughout the several views.

General description.Briefly described, the

machine is a four-stage compressor having portion 0 the four compression cylinders with inter-coolers arranged in circuit followingthe respective.

of a motor which constitutes the motive power. The machine, essentially, consists of an electric motor, the armature shaft of which is extended and formed into cranks at either end, which engage Scotch cross-heads located in crank casings formed integral with the motor casing on each side of the motor and outside the armature bearings.

Secured to each of the crank casings at diametricallyopposite points, and extending in opposite directions, are two com ression cylinders; the respective pistons of w ich are secured to the corresponding cross-head and operate alternately. From each of the cylinders, exce t the last in the series, the air is discharge into inter-coolers, and from the last cylinder it is discharged into the aftercooler. The first and second inter-coolers are constructed substantially alike, being so constructed that the air is conducted through said inter-cooler around and outside of a series of pipes throu h which the cooling medium is conveyed. ln the third intercooler and after-cooler the arrangement is reversed, and the air is conducted through a series of (pipes, while the cooling medium is are provided with central bores through.

' which 011 is forced by a rotary oil-pum secured to the crank of the armature sha t on the end opposite the pump for cooling medium. By this means, oil is supplied under pressure to the various bearings of the armature shaft and crank to the Scotch cross heads, the brasses of which are cushioned on thin films of oil, thus obviating the necessity for a take-up adjustment and rendering the Scotch-cross-head efficient and successful where it has hitherto been a failure.

The air enters the first or low pressure cylinder at atmospheric pressure and tempera ture in thiscylinder it is compressed, and by this compression heatis developed. In its passage through the first inter-cooler the temperature is reduced to substantially normal which likewise reduces its bulk. Entering the second stage cylinder at substantially normal temperature, it"is again compressed and heat again developed. This re-heating and cooling is repeated at each stage of compression to the end of the system.

Data/ll description; general structure.The general structure is best illustrated by Figs. 1 and 2. The motor casing is preferably formed in two parts, an upper portion, a, and a lower portion, a, which are connected by suitable bolts. The crank casings, (1, are formed integral with the motor casing and outside the bearings, (1 of the armature shaft, a. The armature shaft, a (Figs. 5

'and 6-) is formed with an integral crank, 0.

at each end thereof engaging the Scotch crosshead hereinafter described. The armature shaft and crank pins have oil channels, a, and

a, which are connected with the different bearings in such manner as to supply oil to the various crank and shaft bearings under pressure from the pump secured to one of the cranks a A balance disk, a is secured to the armature shaft ad'acent to each crank, and in addition to its alancing functions it consists in distributing oil to the armature bearings, as hereinafter described.

The armature bearings are best shown in Figs. 7, Sand 9, and consist of the bore, a, intermediate the crank casing, a and the motor casing into which are fitted the four bushing parts 03, a a and a", which are shaped on their adjacent sides to conform to the armature shaft; auxiliary parts, a, are provided on which the bushing parts, a are supported. On diametrically opposite sides of the bore, a", are tangent bores, a, having longitudinally movable members, a, having bevel faces coincident with the beveled outer faces of the bushing parts,

a). The members, (1, are movable within the bores, a, by means of screws, a mounted in plugs, a, screwed into the upper ends of the bore, a, and provided with suitable lock-nuts. By means of the screws, 0 operating the members, a, the bushing parts, a, may be adjusted laterally in either direction to compensate for wear or to secure alinement of the bearings. The bushing member, a, is vertically adjustable by means of an adjusting screw, a". The bushing, a, is referably formed with recesses as shown an is provided with oil ducts. (1- An opening closed by a suitable cap, a, is provided for the inspection of the bearing.

On the inner side of the crank casing, a and above the armature bearing is an inclined channel, a, leading to a point immediately above the armature shaft, and having a duct leading therefrom to the recess, a

of the bushing part, a. Oil is contained in the lower part of the casing, a at adepth above the )eriphery of the balance disk, a. As the disk, a revolves, the oil is carried .upward and thrown against the top and sides of the crank casing, 0?; as it descends it is caught by the channel, a, and conducted within the armature bearing. \a ithin the crank casing, a are located the Scotch crossheads, I), having the guides, b, which are supported by suitable bearings, 5 secured to the crank casing at diametrically opposite points.

Within the bore of the crank brasses, b

is a eripheral groove, 1), registering with the oil uct of the crank pin, and from'which lead oil. ducts, b, to the bearing surfaces of the brasses. By this means, a generous supply of oil is conducted under pressure to the bearing surfaces forming athin film of oil upon which the brasses cushion. Under such conditions, there ill be no perceptible wear of the parts and such wear as may possibly occur it ill be compensated for byfga thicker film of oil.

The Scotch crosshead has not been a popular form of construction heretofore, for the reason that the slight clearance of the sliding block in the yoke, which is necessary for a sliding fit has usually allowed the sliding block or wrist-brass to hammer in the yoke, making excessive noise and causing a deterioration of the parts. construction above described, wherein oil under pressure is supplied to cushion, adjust and lubricate the working parts, the Scotch However, by thecrosshead is rendered successful andeflicient; i

Secured to the crank casing, a {upon one;

' ets to the bottom of the 1 .der, 0,

respectively. Connected in a similar manner to the crank casing on the op osite side of the mo'torcasing, aa, are t e second and third stage compression cylinders, e and f, respectively.

The first, and third stage intercoolers, d and g, are secured by suitable brackets to the upper ortion', a, of the motor casing. The second stage intercooler, d, and the aftercooler, g, are secured insuitable brackrespective crank casin s, 0 y p In 1g. 2 is shown the centrifugal pum h by which the cooling medium is supplied to the various 'intercoolers and aftercooler. The outlet conduit from said coolers is indicated at h. It will also be noted that the cooling medium is introduced into each of the various cylinders and coolers at substantially thelowest point and withdrawn therefrom at the highest bility of air collectlng in the water jackets and cooler chambers.

An oil cooler, j, is provided with suitable connections to the respective crank casings, a andthe oil pump, '5.

All, the above mentioned arts will be hereinafter fully'described in etail in regular order. i

Low pressure cyZimler.The low pressure cylinder, 0, consists essentially of the cylinsurrounded by the water s ace or jacket, 0 through which is conducte a current of water for absorbing the heat developed during the operation. The water is conducted to the water jacket, 0 through the pipe, 0 from the outlet of the first intercooler, vd, and after circulating about the cylinder, 0, is conducted throu h the outlet pipe, 0, to the discharge pipe, 7%; the course of the water being indicated by the arrows.

- The piston, 0 of the low pressure cylinder is attached to and in reality forms an extension of the guide, I), of the cross-head, b. The air intake is indicated by c. The air passes from the intake, 0, into the interior of the barrel, 6, through 0 enings, c and thence through a suitable va ve in'the pistonhead to the cylinder, 0 The preferred valve is an inertia valve as shown in Fig. 3. In this construction the piston head is provided with a series of openings, e and a central stud, c", on which is mounted a disk, 0

1 having a'series of openings offset in the arregister with those of the rangement with the openings, e plate, 0", is also secured to the provided with a series ofo A'keeperpiston and enmgs which isk, 0 The keeper-plate, c, is somewhat separated from the piston-head forming a chamber in which the disk, 0 is located and ermitted a slight movement longitudinal to t e piston.

fI-n'o eratio'n .as the rston moves on the re- P P I: stroke, the inertia will cause the disk, c 2,;g.-to move into proxlmity'with the keeperpoint, 'to avoid the possi-- the inlet-p plate, o with the openings of which the (118k openings register and the air will have. free passage through the openings, 0 and,

tegral with the cylinder-head, throu h which itis conducted to the inlet, d of t e first intercooler, d. In the drawings, but one outlet valve 0 is shown; however, three such valves are preferably employed.- First and second intercooZers.Inasmuch as the construction of the first and second intercoolers, d and (1 respectively, is identical, a detailed description of one will be a plicable to both. In Fig. 4, there is sl iown a longitudinal section of the second intercooler, (1 This intercooler consists of a cylindrical casing, d provided at opposite ends with heads, (i in which are supported the o posite extremities of a series of pipes, d". To permit the unequal expansion and contraction of the parts, the loosely connected in the heads, and each ipe is provided with packing glands, at. he casing, (Z contains a series of baffleplates, d, by which atortuous passage is given to the air which is introduced through i e, d", from the second compression cylm er hereinafter described, and withdrawn through the outlet, d, to the third com ression cylinder. The water is introduce through the inlet,-d (Fig. 4), to a chamber, d yadjacent to the head, (i and communicating with the pipes, d The water is passed from the chamber, (Z through the pipes, d, around which the air is circulated, and in a direction contrary to the current of air, to a chamber, (2, at the opposite end of the intercooler from which it passes through the outlet pipe, d, to the water-jacket of the second stage compression cylinder.

1 Referring to the first intercooler, the construction is similar to that just described.

The air is introduced to the first intercoolerfrom the first compression cylinder through the inlet, d, and from the intercooler to the second cylinder through .the outlet, (2 The water is passed in the reverse direction from the water-inlet, (1, to the outlet-pipe, 0 by which it is conducted to the water jacket'of the first stage cylinder, as before mentioned.-

There are provided for the various intercoolers suitable drains (not shown) of 0rd i-' construction, for removing moisture nary which may be preci itated through condensationmlbifpon the coo g ofthe air.

Sec stage cg Zmder.-The second comp1 es, (1, are- 'pression cylinder e is secured to the crank casing, a, on the side of the structure opposite the lowressfure cylinder, 0. It conslsts oi the cylin er, e surrounded by the water jacket, e The iston, e is formed integral with the barrel, E of the Scotch cross-head,- b. The water supply for the water jacket, 42*, is conducted (as indicated by the arrows in Fig. 4) from the intercooler, (2 through said jacket and is discharged from the outlet, e, to the common discharge pipe, k

Formed in the cylinder head and a ortion of the cylinder body is an air conduit divided by a partition, 6 into an inlet conduit, e", and an outlet conduit, e Between the inlet conduit, e, and the cylinder, e is located one or more inlet valves, e and leading from said cylinder and the outlet conduit, e", is an equal number of outlet valves, 6 In the drawings, but one inlet and one outlet valve is shown, however in practice two of each of said valves are preferably employed.

Upon the rearward stroke of the piston, 0 the air is drawn from the first intercooler, d, through the outlet, d, and the inlet conduit, e, and valve, 6*, to the cylinder, e upon the forward movement of the piston 6 the air is ejected through the outlet valve, e", and conduit, e", and the inlet pipe, (2", of the second intercooler into said cooler through which 'it passes as before described to the third compression cylinder.

.. Third stage and high pressure cglinders.-

\ The third' stage and high pressure cylinders being similar in'construction, and differing only in size, a detail description of one will be "equally applicable: to the other.

The third stage cylin er, f is secured to the crank cas ing, a diametrically opposite the second stage cylinder, 6. It consists of a casting having a central bore, f ,.forming the cylinder pro er, and a series of peripheral flanges, Whic form baflle-plates of a water jacket, formed by the inclosing jacket, 1. The piston, f, is attached tothe cross-head, b, and is provided with a packing gland, f An inlet conduit, f and an outlet conduit,

f communicating with the bore, f by by arrows means of inlet and outlet valves, f f respectively, are formed in the cylinder casting. Upon the rearward stroke of the piston, f the air is drawn from the second intercooler, d through its outlet pipe, (1 and the inlet conduit, 1', and inlet valve, f to the bore, f and upon the forward stroke of the piston is ejected through the outlet valve, f and outlet conduit, f to the pipe, f, by which it is 'conducted to the third mtercooler, g. Thecooling medium for the third stage cylinder is conducted, as shown in Fig. 4, from the third inter: through the water jacket of said cylinder and discharged through the outlet,

to the common discharge pipe, h. It will be noted that while the discharge opencooler, g,

opposite ends used. as a cooling medium is sup ing is centrally'located with regard to the end 7 of the cylinder, a conduit, f extends within the water jacket, f, in order that the-discharge water will 'be drawn from substantially the highest point of the jacket.

' The third intercooler' and afterco0Zer.-The air assing through the pipe, f ,"from the from which it is conducted through the connecting pipe, g, to the high pressure cylinder, f. T e cooling medium for the third cooler and compression chamber enters the cooler at y and after leaving the cooler is conducted through the outlet, g, to the third cylinder, as indicated by arrows, Fig. 4, from which it is discharged, as before mentioned, a

through the outlet, f

Since the construction of the third stage cooler, g, and the aftercooler, g, is similar, a

detailed description of the latter with refer thir cylinder enters the thlrd-intercooler, g,

ence to the longitudinal section shown in Fig.

3' will apply equally to both. The aftercooler, g, comprises the cylindrical casing, g having secured thereto the recessed or chambered-heads g-g A series of pipes, are located within the casing, g with their ends secured in the head,'g while the are loosely mounted in the head, g, to j and 'contraction of the various parts. The loose ends of the pipes, g, are provided with ermit the unequal expansion packing glands, g". The air is conducted to the aftercooler from the high pressure cylinder, f, through 9. pi e, g and enters a chamber, g, in the hea 9 which communicates with the respective pipes, 9 directly 0 posite the air intake, is provide with a re ucing plug, g inorder that the air may be distributed to the other pipes and prevented from rushing through the central pipe. From the res ective pipes, g, the air empties into a cham er, g in'the head, g, from which leads the offtake g, to the comres sed air reservoir. The cooling medium is introduced to the aftercooler through the inlet, g, and is withdrawn through g and is conducted, as indicated by arrows in Fi 3, about the high-pressure cylinder, f, whic corresponds to the descriptlon before made of the third stage cylinder. From the hi hpressure cylinder, thecooling mediumis is- The P p 9*,

charged through the outlet, f, to the common discharge pi e, h;

Pump for coo ing 'med'ium.-The water plied to the various coolers and correspondmg cylinders under pressure by means of a rotary pum h, secured to the cover, 0, of one of the cran casings, a I The pum h, is ill strated'in Eggs. l2 and 13 of the i'awings. It consists o the circular casing, integral with the co eact, the cover, h An intake pipe, h, leading from the sourceof supply and an ofi+take pipe, h, from which the water is distributed,

h", preferably formed and fitted with.

by various branches, to the respective coolers, are connected with the casing, W, at diametrically opposite points. Eccentrically mounted within the casing, h is a rotary member, h, provided with spring pressed blades, N, which at all-times are pressed in contact with the inner periphery of the easing, 71-. The rotary member, h, is )rovided with a shaft, h, mounted in a suitable hearing in the cover, a, and extending within the casing, a lhe casing, b and rotary member, 71-, are so located that the axial line of the shaft, it, will be coincident with that of the armature shaft, at

Secured to the inner end of the shaft, h, is a crank arm, h", having therein an opening preferably a slot, as at h, to engage a stud, t, in the end of the crank, ar'f. By this means, the rotary member, h, is driven in unison with the armature shaft, a, and by the action of the blades, h, the water is drawn in through the intake, h and discharged through the ofl take, h, to the various coolers.

Oil-pump and c0oZer.As before mentioned, the armature-shaft, a and cranks, a, are provided with central bores, a, and

' lateral ducts, a, by which oil is supplied, un-

der pressure, to the various bearings from a pump, i, connected to one of the cranks, a as shown in Figs. 5 and 8. The pump, i, consists of the circular casing, i having the cap, i fitted thereto. An intake, 5 leads into the casing. Within the casing, i is eccentrically mounted in suitable bearings, a ifotary member t having formed integral therewith a shaft, '5 A central bore, '5, extends longitudinally through the rotary member, '5 and shaft, '17. There are carried b the rotary member, i spring actuated blades, which continuousl contact the inner walls of the casing, '5 an o crate in a man ner similar to the blades, L ,.Of the water pump, it, to draw the oil through the intake, t and discharge it through an opening, 03, in the casing, i, located diametrically opposite the intake, i The-opening, i, in the casing, i, registers with a conduit, i in the cap, i which conduit in turn registerswith the bore i of the rotary member, i cured to the shaft, i is a crank member, 2'", having an enlarged end, i adapted to be secured to the end of the crank pin of one of the cranks, a as in Figs. 5 and 8. The throw of the crank member, i", is equal to that of Hie crank, a whereby the body of the oil pum i will remain stationary while the cran member, t, revolves with the crank,

a. Within the crank member, i, is a conduit, '5, connecting the bore, i, of the shaft,

t and the bore, a", of the crank, a Thus as the armature shaft a rotates, the rotary member, '5, through the crank member, 6 will rotate in unison and the oil be drawn through the intake-pipe, i and discharged through the opening, 'i", thence through the conduit, i and the bore, '13, of the rotary memberyi to the conduit, '11, by which it is conducted to the bore, a", of the crank, a The oil supply is located in the lower part of the cran casings, a A portion of the oil forced by the pump, 2', through the armature shaft, a, is discharged into the casing, a on the side opposite said pump, which casing would, eventually, receive the entire oil supply if means were not provided for returning it tothe pump, '11. To maintain the oil inequilibrium, and further cool the oil which becomes heated in its passage through the bearings, the oil cooler, j, is provided, extending below the portion, a, of the motor frame, and having connections 7" with each of the casings, o in order that the supply of oil to the pump, 6, may be cool, there is provided a pipe, j leading from the oil-cooler, j, to a point within the casing, a Into the pipe, 7' extends the erforated end, "L of the Oll intake, *3. By t is means, the oil supplied to the armature and crosshead bearings is drawn direct from the cooler, 7'. The construction of the oil-cooler, 9', is similar to that of the aftercooler, 9 the oil being circulated through the pipes while the water is passed in the opposite direction around claim "1. In an air compressor, the arrangement of the circuits of air and cooling medium b arranging a plurality of cooling devices wit a plurality of compression devices and a pump and conduits directing the cooling medium from the um direct to each cooling device, means or discharging the cooling medium from each cooler to the compressor jacket, and means for directing the air from each compressor cylinder to a cooler in a di rection opposite to that of the cooling medium circuit, substantially as specified.

2. In an air compressor, the arrangement of the air and cooling medium circuits comprising a plurality of coolers and a plurality of compression cylinders, means for forcing the cooling medium direct to each cooler, and means for conducting the cooling medium through each cooler and thereafter to its associated compressor, and means direct-1 ing the air from each compressor cylinder through its associated cooler in a direction reverse to that of the cooling medium circuit, and means for discharging the air from the high stage com ressor cylinder to a reservoir, substantia y as specified.

3. In-an air compressor, the arrangement uninclosed conduits within each cooler for the air and cooling medium, means for forcing the-cooling medium through said mclosed conduits in the low stage cooler and through the uninclosed conduits in the higher stage cooling devices, and means for directing the air from a compressor cylinder to its associated cooling devices in a direction opposite to that of the cooling medium circuit, substantially as specified.

4. In an air com ressor, the arrangement of the air and coo ing medium circuits by combining a plurality of multiple stage compressors with a plurality of coolers, a pump or forcing the cooling medium direct to eac cooling device, and separate conduits in the cooling device for the air and cooling medium, and means conducting the cooling medium for the low stage cooling devices through one set of said conduits and the air from the compressor cylinder through the other set of conduits in a direction opposite to that of the cooling medium circuit and in the higher stage cooling devices, means for forcing the cooling medium through the con-' duits corresponding to the air conduits in the low stage cooler, and theair through the conduits corresponding to the cooling medium conduits of said low stage cooler, substan- ,tially as specified.

5.- In an air com ressor, the arrangement of the air and coo ing medium circuits by combining a plurality of compressors with a plurality of coolers, a plurality of pipes 'with- 1n the coolers, and a plurahty of conduits additional to said pipes, a pump for forcing the cooling medium direct to each cooler and through the pipes in the first stage coolers, and means for directing air through the other conduits in the low stage cooler in a direction opposite to that of the cooling medium circuit, and means for directing the air through the pipes in higher stage coolers v and for forcing the cooling medium through the other conduits inva direction opposite to thait of the air circuits, substantially as specie r I I 6. In an air compressor, the arrangement of the cooling medium and air circuits by combining a plurality of compressors with a plurality of coolers, a pump for forcing the cooling medium direct to each cooler and into the bottom thereof and directing the coolingmedium from the top of the cooler to its associated compressor, and means for directing the. air throughsaid cooler in a direction oppositeto that of the circuit ofcooling medium, and means for thereafter directing the air.:to the next higher stage compressor, substantially as specified. t

7'. In an air compressor, the combination of an electric motor with a main casing see c cured to said motor, a plurality of compressors, a plurality of coolers, and a pump cooperating with said coolers operated by said] motor and directing the cooling medium direct to each cooler, a plurality of conduits connecting the compressors and coolers, and;

means for entirely supporting all of said devices from the main casing of said, motor, substantially as specified.

8. In an air compressor, a casing, an armature shaft, an electric motor secured thereto,

a series of compression chambers connected to said armature shaft, and cooling devices following in circuit each of said compression 8o chambers, and a pump located on said casing and operated by the armatureshaft'of said motor for supplying a coolin medium to. each of said cooling devices, su stantially as specified.

9. In an air compressor, an electric motor, compression chambers supported upon the motor casing, cranks upon the armature shaft of said motor, driving connections from said'cranks to the pistons of said cylinders, an internal oil channel extending through said armature and cranks, lateral ducts leading from said channel, and an oil pump driven by said armature shaft and connectedto said internal oil channel for supplying'oil, under pressure, through said channel and ducts to the various bearings, substantially as specified.

10. In an air compressor, an electric motor, oppositely disposed comiares'sion'chambers' and pistons supported on the casing thereof, a crank formed on the armature shaft of said motor, a Scotch crosshead engaging said crank and operating the pistons of said compression chambers, means for supplying oil under pressure to said cross head through said cranlsto cushion and adjust the brasses'of said crosshead, and compensate for the wear thereof by a film of oil of greater or less thickness, substantially as specified. r

11. In an air compressor, an electric motor, a plurality of compression chambers operated by said motor, intercoolers connected in circuit with and intermediate said cham- I bers, an aftercooler following in circuit the high pressure chamber, means for sup lying cooling medium directly .to each of t e re, spective intercoolers and aftercooler, means for conducting the co'olingmediiun from each of the intercoolers and aftercooler about the compression chamber preceding in circuit grel respective coolers, substantially as speci- 12. In an air compressor, anelectric moarmature shaft of said motor, direct connections between said cranks and the pistons of the respective compression chambers, intercoolers intermediate said chambers, a pump directly connected --to and operated by the armature shaft for supplying cooling medium to said'intercooler, a ump'directly connected to the opposite end of the armature shaft for su plying oil,.under pressure, to the va rious earings, substantially as specified.

14. In an air compressor, an electric motor, a crank located on the armature shaft thereof, oppositely disposed compression chambers, a Scotch crosshead en aged by the cranks of the armature shaft, plstons for said compression chambers rigidly connected to said crosshead, an oil pump connected to v and operated by said crank, a conduit in said crank leading from said pump, a'lateral duct leading from said conduit to-the bearing of the cra'nk, and crosshead brasses, oilconduit's in the'crosshead brasses leading to-the bearings of. said brasses and crosshead, substantially as specified. V

-I 15. In-an air compressor, an electric motor, oppositely disposed'compression chambers, a crank formed on the armature shaft of said motor, a Scotch crosshead enga ed by said crank, the brasses of which are devoid of mechanical adjustment, pistons connected 40 to said crosshea a pump operated by said armature shaft for supg ylng oil, under ressure, to said crosshea whereby the ear- -ings of the brasses on the crosshead will be automatically ad'usted by the thickness of the intervening m of eil, substantially as specified.- V

16. In an air compressor, an electric motor, a crank formed on the armature shaft of said motor, acrank casing within which said crank revolves, and adapted to form an oil reservoir secured to the motor casing, and adjacent to the armature bearing, compression chambers supported on said crank casing, pistons operatm Within said chambers,

and actuated by sai crank, a balance disk secured to the armature shaft with a portion of its periphery submer ed in the oil within the crank casing, an o collecting conduit secured to the interior of the crank casing,

and leading to the armature bearing, substantially as specified. I 17. In an air compressor, a compression chamber, a cooling jacket surrounding said chamber, an intercooler, a piston operating with said compression chamber, means for air conduit leading rorn the compression said compression chamber, and communicatformed 'integra reciprocating said piston, a chamber within sai piston 0 en to the air intake, a valve in the head otsaid piston, leading from said chamber to the com ression chamber, an

chamber. to the intercooler, an outlet valve 'from said compression chamber into said air conduit, a conduit for cooling medium leading from the intercoolerto the cooling jacket, and a discharge conduit leading from said coolin jacket, substantially as specified 18. 11 an air compressor, a plurality of. compression chambers, pistons therefor,

means for actuating said pistons, .a cooling jacket surrounding said chambers, an 'intercooler' in circuit between said chambers,

an air conduit leading from the first compression chamber of the series to said intercooler an air conduit leading from said intercooler to the second compression chamber of the series, a supply for cooling medium, a conduit leadingtherefrom to said intercooler, means for circulating the cooling medium through the intercooler in a direction con-' trary to that of the air, a conduit leading from the intercooler to thecoolingjacket of 1 the first compression chamber of the series,- and a discharge conduit leading from said coolin jacket, substantially as'sp'ecified- 19. 11 an air com ressor, a compression chamber, a piston t erefor, means for actuating said piston, air cooling devices connected in circuit with said compression chamber and on opposite sides thereof, an, air conduit formed in the head of said -compression chamber and communicating with said cooling devices, a partition dividing said conduit into an intake and an outlet portion, an intake valve and an outlet valve in the head of ing with the res ective portions of said conduit, substantia ly as specified.

.20. In an air com ressor, a compression chamber, a piston t erefor, means for actuating said iston, an air inlet and an air outlet in sai compression chamber, a cooling jacket surrounding said compression chamber, baflielates in said cooling jacket l with said compression chamber, an inlet for cooling medium to said coolin jacket, an outlet leadingfrom substantia y the-highest oint of said jacket, substantially as spec' ed.

21. In an air compressor, a compression chamber, a Scotch crosshead, a pistoncon- 12 nected to said crosshead and operating within said compression chamber, air inlet and air outlet valves in said chamber, peripheral flanges. on said com ression chamber, a jacket surrounding said 0 amber, y

and flanges. forming a cooling chamber withm which said flanges constitute bafiieplates, and an inlet and an outlet in said coolinghjlacket, substantially as specified.

an air compressor, compression air cooling devices, a plurality of com chambers, operating devices therefor, an

{electric motor, a crank formed on the armav nel from the discharge of said ump through said pump crank to the oil'c annel of said armature crank, substantially as. specified. 231 In an air compressor, a plurality of pression chambers, means for actuating the pistons of said compression chambers, a pum .'for supplying cooling medium, indepen ent conduits leading to each of the air cooling devices, a condu1t leading from each of the respective cooling devices to'the cor responding compression chamber, and a discharge conduit leadin from each of the compress on chambers, su stantially as specified.

24. In an air. compressor, compression chambers, cooling devices, an electric'motor, a crank formed on the armature shaft of said motor, a rotary pump, a crank for operating said pump, connected to the said crank (in the armature shaft, substantially as specified;

.25. In an air compressor, a motor, oppositely disposed compression chambers and" pistons supported in crank formed-on the s aft'of-said motor, a

roximity thereto, a

Scotch crosshead engaging said crank and o crating the pistons of said compression c ambers, oil conduits in said shaft and crank connecting with said crosshead and its bearings, and an oil pump driven by said shaft and connected with said oil conduit for supplying oil under pressure to said a cooling medium to said intercoolers an to said Water jackets, and anoil pump operated by saidmotor for supplying a continuous flow of oil to the working parts, substantially as specified.

In-testimony whereof, we have. hereunto set our hands this 14" day of August AD.

1905. a .AUGUSTINE J. POCOCK.

- RICHARD E. ,ALLGIRE. Witnesses:

E; F. GALLAUDET, J. MARTIN. 

